LM2576T-3.3/LF03

Voltage Regulators - DC DC Switching Regulators Overview

The LM2576T-3.3/LF03 is a monolithic integrated circuit from the LM2576 series, functioning as a step-down switching regulator (buck converter). It provides a fixed 3.3V output with a guaranteed maximum load current of 3A. The device operates with an input voltage range up to 40V and utilizes a fixed internal oscillator frequency of 52kHz. It incorporates internal frequency compensation and requires minimal external components for implementation. The unit features cycle-by-cycle current limiting and thermal shutdown protection.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrated buck converter topology with fixed 52kHz oscillation
• Built-in thermal shutdown and cycle-by-cycle current limiting
• Fixed 3.3V output with ±4% tolerance under specified conditions
• External shutdown capability for low-power standby modes

Voltage Regulators - DC DC Switching Regulators Applications

• Efficient replacement for three-terminal linear regulators in power supplies
• Pre-regulator stages for downstream linear regulators
• Direct powering of microcontroller units (MCUs) and digital logic
• Battery-powered systems requiring high efficiency and low heat dissipation

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the manufacturer origin, as National Semiconductor is now part of Texas Instruments. Confirm the specific suffix LF03 corresponds to the intended package variant and lead-free status. Ensure compatibility with existing bill of materials regarding pinout and thermal requirements before finalizing procurement decisions.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a fixed 3.3V output is required with up to 3A load capacity. It is suitable for designs prioritizing simplicity and cost-efficiency over high-frequency operation. Consider the 52kHz switching frequency implications on inductor size compared to modern higher-frequency alternatives.

Voltage Regulators - DC DC Switching Regulators Part Context

This component belongs to the LM2576 family of SIMPLE SWITCHER regulators. Originally developed by National Semiconductor, the product line has been transitioned to Texas Instruments. The T suffix indicates a TO-220 through-hole package, while the -3.3 denotes the fixed output voltage level.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Compatible replacements include LM2576T-3.3/NOPB and LM2576T-3.3G. Verify pinout compatibility and thermal performance characteristics when substituting with variants from different manufacturers such as onsemi.